Device for adjustment of a backrest inclination

ABSTRACT

A device for adjustment of the backrest inclination for a backrest of a seat in a motor vehicle includes a backrest connected to a rotating locking device. The device may be locked in defined lock positions for adjustment of the inclination, by means of a locking element which may be positionally adjusted. The locking element may be placed in a defined spatial position, by means of at least one operating mechanism, such that the locking element is in a position to be locked in only a partial number of the possible locking positions. A defined adjustment of the inclination is thus achievable in a simple manner.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a National Phase Patent Application of InternationalApplication Number PCT/DE01/03700, filed on Sep. 21, 2001, which claimspriority of German Patent Application Number 10 228.7, filed Sep. 21,2000.

FIELD OF THE INVENTION

The invention relates to a device for the adjustment of a backrest of aseat.

BACKGROUND OF THE INVENTION

Motor vehicles such as cars, trucks, vans, sport utility vehicles, busesand the like, include seats which are desirably adjustable. It isgenerally desirable to provide such a motor vehicle seat with a backrestthat is adjustable to various degrees of inclination, that is, multiplepositions to provide versatility and comfort for various users. It isfurther desirable to adjust the backrest in a simple manner and tosecurely lock the backrest in its various locked positions.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a device in whichdefined backrest inclinations can be adjusted in simple manner.

This is achieved according to the invention through a device having thefeatures of a rotatable detent locking means which is connected to thebackrest. In order to adjust the backrest inclination the detent lockingmeans can be locked in defined detent positions by a locking elementwhich is adjustable in position. The locking element can thereby bebrought into a defined spatial position by means of at least oneoperating mechanism such that, in one position, the locking element canbe locked in only a partial number of the possible locking positions.

Different inclines of the backrest can be readily controlled by matchingthe defined detent locking positions and the defined positions of thedetent locking means.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be explained in further detail with reference tothe embodiments illustrated in the drawings in which:

FIG. 1 shows a side view (drive direction to the right) of an exemplaryembodiment of a device for adjusting the backrest incline;

FIG. 2 shows a side view (drive direction to the left) of an exemplaryembodiment of the device for adjusting the backrest incline;

FIG. 3 is a partial cross-section illustration of the side view of FIG.2 showing additional elements not shown in FIG. 2;

FIG. 4 shows a side view of the exemplary device shown in FIG. 1 withthe device in a first operating position with the backrest unlocked;

FIG. 5 shows a side view of the device shown in FIG. 4 with the devicein the first operating position with the backrest locked;

FIG. 6 shows a side view of the exemplary device shown in FIG. 1 withthe device in a second operating position with the backrest unlocked;

FIG. 7 shows a side view of the device shown in FIG. 6 with the devicein the second operating position with the backrest locked;

FIG. 8 shows a side view of the exemplary device shown in FIG. 1 withthe device in a third operating position with the backrest unlocked;

FIG. 9 shows a side view of the device shown in FIG. 8 with the devicein the third operating position with the backrest locked;

FIG. 10 shows a side view of the exemplary device shown in FIG. 1 withthe device in a fourth operating position with the backrest unlocked;

FIG. 11 shows a side view of the device shown in FIG. 10 with the devicein the fourth operating position with the backrest locked;

FIG. 12 shows a perspective view of an exemplary embodiment of thedevice of the present invention in the unlocked first operating positionsubstantially as shown in FIG. 4;

FIG. 13 shows a perspective view of an exemplary embodiment of thepresent invention in the unlocked second operating positionsubstantially as shown in FIG. 6;

FIG. 14 shows a perspective view of an exemplary embodiment of thepresent invention in the locked second operating position substantiallyas shown in FIG. 7;

FIG. 15 shows a perspective view of an exemplary embodiment of thepresent invention in the unlocked third operating position substantiallyas shown in FIG. 8;

FIG. 16 shows a perspective view of an exemplary embodiment of thepresent invention in the unlocked fourth operating positionsubstantially as shown in FIG. 10; and

FIGS. 17 to 20 show perspective views of the device according to thebackrest inclination adjustment device of the present invention mountedin a seat structure.

DETAILED DESCRIPTION

FIG. 1 shows in a side view a device for adjusting the incline of abackrest 1 in a motor vehicle. The backrest 1 which is showndiagrammatically is thereby part of a seat (not shown here) which may bethe seat in an automobile, truck, van, sport utility vehicle, bus orother motor vehicle. The part of the seat is thereby a side part 50which can be moved forwards and backwards horizontally (right to left orvice versa in FIG. 1). In FIG. 1 it is assumed that a person seated onthe seat is looking to the right in the drive direction.

In an exemplary embodiment, the device according to the invention isshown using the example of a backrest 1 in a van and in which the deviceadjusts the backrest 1 in four definable positions. Basically theinvention relates however to any adjustment of generally more than twopositions of the backrest 1.

To provide such adjustment, the invention provides a detent lockingmeans which, in the illustrated embodiment, is a cam disc 2 with fourrecesses 3, 4, 5, 6. Other detent locking means, including membershaving other shapes and different numbers of recesses, may be used inother exemplary embodiments.

The backrest 1 is connected eccentrically to the cam disc 2 through aconnector 16 so that swivel movement of the backrest 1 is converted intoa rotational movement of the cam disc 2.

The exemplary cam disc 2 has here four recesses 3, 4, 5, 6 which can bebrought into engagement with a detent locking element such as lockingbolt 7 on a locking lever 8 which is pretensioned with spring force (seeFIGS. 4 to 11). The recesses 3, 4, 5, 6, when the locking bolt 7 isreceived therein, thereby correspond to different inclines of thebackrest 1. Recesses 3, 4, 5 and 6 correspond to the first, second,third and fourth exemplary locking positions, respectively and the camdisc 2 is in locked position when locking bolt 7 is secured within oneof the recesses 3, 4, 5, or 6.

FIG. 1 shows the third operating position (see also FIGS. 8, 9) used toexplain the interaction of the individual component parts. Thirdoperating position corresponds to recess 5.

The third operating position relates to an “easy entry” function of aseat where climbing into the back of the vehicle is to be made easier.The backrest 1 is thereby folded relatively far forwards and sliding theseat forward is also possible.

Sliding the seat forwards thereby becomes possible by a cam 17 of thecam disc 2 actuating an articulated lever chain 31, 32, 33. Thearticulated lever chain 31, 32, 33 consists of three articulated leverswhich are each able to swivel about respective rotary points.

In the illustrated operating position the cam 17 presses a firstarticulated lever 31 which is pretensioned against the same in acounterclockwise direction. A second articulated lever 32 which isconnected rotatable to one end of the first articulated lever 31 isthereby swivelled clockwise.

At the end of the second articulated lever 32, which is opposite theconnection between the first and second articulated levers, the secondarticulated lever 32 is connected rotatably to a third articulated lever33. The clockwise rotation of the second articulated lever 32 results inthe counterclockwise swivel movement of the third articulated lever 33.

At the free end of the third articulated lever 33 is a hook which can belocked with a fixed part of the motor vehicle. This is showndiagrammatically as au opening in FIG. 1. The hook is drawn out from theopening through the aforementioned swivel movement of the thirdarticulated lever 33 so that the locking action is released and the seatbecomes adjustable.

In another exemplary embodiment, the force transfer from the cam disc 2to a locking means (e.g. a hook) can be produced using a Bowden cable.

A series of component parts are used for controlling the locking bolt 7relative to the four recesses 3, 4, 5, 6.

A first rotational element 11 is mounted rotatable on the same shaft asthe cam disc 2. The first rotational element 11 has a hooked follower 15which can transfer a force to a second rotational element 10 lyingbetween the cam disc 2 and the first rotational element 11. The secondrotational element 10 is only visible in part in FIG. 1 and hassubstantially the shape of a large “L” in an exemplary embodiment. Thesecond rotational element 10 is also mounted on the same shaft as thecam disc 2.

The rotational elements 10, 11 and a lever (not shown in FIG. 1) areoperating mechanisms for the locking bolt 7 whereby the lever can beoperated independently of the rotational elements.

The first rotational element 11 has a first Bowden cable fixing point 13on which a first Bowden cable (not shown) may be fixed. If this firstBowden cable is pulled then the first rotational element 11 is movedclockwise. The first rotational element 11 is in any case designed sothat the rotational movement can only be executed up to a certain angle.After moving in the clockwise direction a part of the first rotationalelement 11 strikes against a stop 20 which is mounted on a componentpart which is not shown. Hereinafter, for reasons of clarity, stop 20 isnot shown in any of the following figures. This stop 20 defines an endposition for the rotation of the first rotational element 11.

The second rotational element 10 has on the short side of the large “L”a second Bowden cable fixing point 12 at which a second Bowden cable(not shown) may be fixed. If this Bowden cable is pulled then the secondrotational element 10 is moved in the clockwise direction. As such,first rotational element 11 and second rotational element 10 areindependently operable.

The long side of the L-shaped second rotational element 10 has a camwhich engages with a slide guide 9 of the locking lever 8. The lockinglever 8 is substantially L-shaped whereby the locking bolt 7 is mountedon the short side. The locking lever 8 is mounted for swivel movement atthe end of its long side.

If the second rotational element 10 is swivelled clockwise then the camwhich is in engagement with the slide guide 9 executes a rotationalmovement which is converted by means of the slide guide 9 into arotational movement of the locking lever 8 in the clockwise direction.This rotational movement leads in turn to the locking bolt 7 beingengaged or disengaged from one of the recesses 3, 4, 5, 6. A clockwiseswivel movement of locking lever 8 thereby leads to disengagement oflocking bolt 7 from the corresponding recess; a counterclockwise swivelmovement of locking lever 8 thereby leads to engagement of locking bolt7 in the corresponding recess, in the exemplary embodiment illustratedin FIG. 1.

The first recess 3 and the second recess 4 are brought into or out ofengagement with the locking bolt 7 through a lever (not shown) whichrotates cam disc 2 and adjusts the position of backrest 1.

FIGS. 2 and 3 show the device for adjusting the backrest inclinationfrom the opposite side of the seat shown previously in FIG. 1; i.e., thedrive direction is to the left in FIGS. 2 and 3. The locking bolt 7 isthereby shown engaged in the first recess 3, which is partially obscuredin FIGS. 2 and 3.

According to the invention the locking bolt 7 can be moved in a definedway so that it can only come into engagement with the associatedrecesses 3, 4, 5, 6 in a predeterminable manner. Operating elements notshown here such as handles, levers, etc thereby ensure that the lockingbolt 7 is each time moved over a certain path and/or angle so thatduring manual swivelling of the backrest 1 a certain backrest incline,i.e. operating position can be controlled and locked.

The first exemplary operating position, shown in FIGS. 4 and 5, isassociated with locking bolt 7 being engaged in the first recess 3. Inthe first operating position the backrest 1 is inclined relatively farbackwards.

The second exemplary operating position, shown in FIGS. 6 and 7, isassociated with locking bolt 7 being engaged in the second recess 4. Inthis operating position the backrest is disposed somewhat steeper.

The third exemplary operating position, shown in FIGS. 8 and 9, relatesto the “easy entry” function, in which backrest 1 is inclined forward,as explained above.

The fourth exemplary operating position, shown in FIGS. 10 and 11,relates to the substantially horizontal arrangement of the backrest 1 inwhich the back of the backrest 1, which appears as the top portion inFIGS. 10 and 11, can be used as a table, for example. In the fourthexemplary operating position, locking bolt 7 is positioned at fourthrecess 6.

For each of the aforementioned operating positions, the device is inlocking position when locking bolt 7 is engaged or secured in theassociated recess.

In FIGS. 4 to 20 the same component parts are given the same referencenumerals as used in FIG. 1 so that reference can be made to thedescription thereof.

The cam disc 2 has a complex stepped external contour which is matchedto the defined position changes of the locking bolt 7. The steps of theexternal contour are thereby each formed by side faces 24, 25, 26 ofrespective recesses 4, 5, 6. For each of respective recesses 4, 5, 6,side faces 24, 25 and 26 are longer in the radial direction than therespective opposite side face of the corresponding recess 4, 5, 6.

For example, the second side face 24 of the second recess 4 is slightlylonger in the radial direction than the first side face 23 of the firstrecess and the opposite side face of the second recess 4. The secondside face forms a stop for the locking bolt 7.

In FIG. 4 the locking bolt 7 is swivelled by a lever (not shown) about acertain angle so that it becomes disengaged from first recess 3 and thecam disc 2 can rotate in a likewise certain angular region underneaththe locking bolt 7.

On operating the lever the locking bolt 7 is disengaged so far that itcan move up to the second side face 24 and then strike against same (seeFIG. 6).

Thus by operating the lever the user can choose between the firstoperating position associated with recess 3 and the second operatingposition associated with recess 4. The locking bolt 7 can be engaged inthe first recess 3 (see FIG. 5) or the second recess 4 (see FIG. 7).

If the user wants to select the “easy entry” position of the backrestand seat (the third operating position), then in the present embodimenthe operates the second Bowden cable (not shown) which is mounted at thesecond Bowden fixing point 12 of the second rotational element 10.

Through the aforementioned swivel movement of the second rotationalelement 10 the locking bolt 7 is swivelled radially through the slidingmechanism of the locking lever 8 relative to the cam disc 2 so that itcan proceed to the third recess 5. The side face 25 of the third recess5 in turn projects radially slightly beyond the peripheral edge of camdisc 2 so that this projection serves as a stop for the locking bolt 7(see FIG. 8). The locking bolt 7 may then become engaged in the thirdrecess 5 in the detent locking action (see FIG. 9).

Opposite the recess 5 lies the cam 17 of the cam disc 2 which asdescribed above operates the articulated lever chain 31, 32, 33 so thatin this third operating position of the cam disc 2, i.e. locking bolt 7engaged in recess 5, the seat is able to slide forward. The combinationof the backrest folded forward with the seat pushed forward enableseasier entry into the vehicle (easy entry).

Through the operation of the second rotational element 10, the lockingbolt 7 is swivelled radially further outwards through the slidemechanism of the locking lever 8 relative to the cam disc so that it canovercome the step of the side face 25 and can pass up to the fourthrecess 6, as shown in FIG. 10. In this position the backrest 1 can bebrought into a substantially horizontal position so that it can be usedas a table, for example. In this position the locking bolt 7 can belocked with the fourth recess 6 (see FIG. 11).

Although the device, according to an exemplary embodiment of theinvention, is described with respect to a cam disc 2 with four recesses3, 4, 5, 6 (i.e. four operating positions), such description is intendedto be illustrative and not limiting of the present invention.

In other exemplary embodiments, more than four recesses can also bearranged on the cam disc 2 in order to enable a larger number ofoperating positions. Thus for example two different “easy-entry”positions can be defined. The detent locking means of cam disc 2 canalso have instead of recesses radially protruding teeth which would be atype of negative image of the cam disc 2 with recesses. In theembodiment in which the cam disc 2 includes radially protruding teeth,the cam disc 2 may include at least one tooth being longer or shorterthan the other teeth.

Also the detent locking means is not limited to being a member having adisc-shaped design. In other exemplary embodiments, the detent lockingmeans may include members which could be cylindrical whereby theindividual steps of the detent locks are formed by a radial staircaselike structure lockable in the axial direction by a detent lockingelement.

FIGS. 12 to 20 show perspective views of an embodiment of the deviceaccording to the invention. The same components are used as in theembodiments of FIGS. 1 to 11 so that reference is made to the abovedescription. The equivalent operating positions to those shown in FIGS.12 to 20 are given in the list of drawings provided above.

The invention is not restricted in its design to the preferredembodiments given above. Rather a number of variations is possible whichuse the device according to the invention even in fundamentallydifferent designs.

1. A device for adjusting the backrest inclination of a backrest of aseat, comprising: a backrest connected to a rotatable detent lockingdevice which, in order to adjust the backrest inclination, is lockablein defined detent locking positions by an adjustable detent lockingelement, wherein the detent element is positionable in defined spatialpositions by at least two operating mechanisms such that, in at leastone spatial position of said spatial positions, the detent lockingelement is lockable in only a partial number of the defined detentlocking positions and the at least two operating mechanisms are operableindependently of each other.
 2. A device for adjusting the backrestinclination of a backrest of a seat, comprising: a backrest connected toa rotatable detent locking device which, in order to adjust the backrestinclination, is lockable in defined detent locking positions by anadjustable detent locking element, wherein the detent locking element ispositionable in defined spatial positions by at least one operatingmechanism such that, in at least one spatial position of said spatialpositions, the detent locking element is lockable in only a partialnumber of the defined detent locking positions, and the detent lockingdevice has a release mechanism through which, in the event of apredetermined inclination of the backrest, locking of the horizontaladjustment of the seat is one of automatically released and locked. 3.The device according to claim 1 or 2, wherein the detent locking deviceincludes a shape with at least one stop to position the detent lockingelement in a certain position and the detent locking element in thiscertain position, is lockable in only a partial number of the detentlocking positions.
 4. The device according to claim 1 or 2, wherein thedetent locking device includes a member that is disc shaped and thedetent locking element is lockable in radially arranged recesses of saiddisc shaped member of said detent locking device.
 5. The deviceaccording to claim 4, wherein at least one of the recesses includes aside face formed radially longer than an opposed side face of thecorresponding recess in order to form a stop for the detent lockingelement.
 6. The device according to claim 1 or 2, wherein the detentlocking device is formed substantially as a toothed wheel wherein atleast one tooth is longer or shorter than the other teeth.
 7. The deviceaccording to claim 1 or 2, wherein the detent locking device includes amember that is cylindrical in shape and has a concentric circumferentialstructure for axially engaging with the detent locking element.
 8. Thedevice according to claim 1 or 2, further comprising a swivel-mountedlocking lever and wherein the detent locking element is disposed as abolt on the swivel-mounted locking lever.
 9. The device according toclaim 8, wherein the position of the detent locking element ischangeable by swivelling the locking lever.
 10. The device according toclaim 9, wherein the locking lever has a slide guide and is connectablewith at least one of the operating mechanisms by said slide guide. 11.The device according to claim 8, wherein the locking lever has a slideguide and is connectable with at least one of the operating mechanismsby said slide guide.
 12. The device according to claim 2, wherein therelease mechanism comprises one of a cam and a Bowden cable connection.13. The device according to claim 1, wherein the backrest forms part ofa motor vehicle seat.